The present invention relates to nitrogen-containing four-membered heterocyclic ring compounds, e.g., azetidines. More particularly the present invention relates to a novel process for preparing such compounds in high yields and purity, and in a simplified manner. Azetidines are a useful class of compounds having beneficial pharmaceutical properties as appetite depressants.
It has been previously known to prepare azetidines via an intermolecular S.sub.N.sup.2 displacement and cyclization of 1-amino-3-halopropane by reaction with caustic. It is further known to cyclize 1,3-dihalopropane compounds directly by reaction with an appropriate amine. It is further known to prepare azetidines by reduction of 2-azetidinones with strong reducing agents such as LiAlH.sub.4. The above processes have been described in greater detail by N. H. Cromwell et al., Chem. Rev., 79 (4), pp. 331-358 (1979).
In U.S. Pat. No. 3,649,618 certain novel 1-(phenylisopropyl)-3,3-dimethyl azetidines having utility as appetite depressants were prepared by reacting an appropriately substituted .alpha.-methylphenethyl-3-halo-2,2-disubstituted propionamides with a reducing agent.